feat: fetch svg from asset path

[danielleroux]

🆕 What is the new behavior?

Activate v3 preview feature with a meta header tag

<meta name="ix-icons:v3-preview" content="svg-path-loading;" />

Define a custom svg fetching path via

<meta name="ix-icons:path" content="/my/path/to/asset/folder/with/the/svgs" />

🏁 Checklist

A pull request can only be merged if all of these conditions are met (where applicable):

• [x] 🧪 Unit tests were added/updated and pass (pnpm test)
• [x] 📸 Visual regression tests were added/updated and pass (Guide)
• [x] 🏗️ Successful compilation (pnpm build, changes pushed)

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